Updated Physical Activity Guidelines Are Out. But Most Teenagers Never Met the Old Ones
By Guest Blogger Sasha Jones
Preschoolers should be active throughout the day to enhance growth and development, and older children and adolescents should do at least 60 minutes a day of various moderate-to-vigorous physical activities, according to new physical activity guidelines released this week by the U.S. Department of Health and Human Services.
Although the new guidelines do not change the amount of time that teenagers and adults should exercise, they do change the standards to include all forms of movement as exercise, even if the activities do not last a full 10 minutes, as the last set of guidelines specified in 2008.
In setting the guidelines, the 2018 Physical Activity Guidelines Advisory Committee conducted a systematic review, addressing 38 questions and 104 subquestions of the emerging body of science supporting physical activity and health. The committee then graded the evidence based on the consistency and quality of the research, and evidence graded as strong or moderate became the basis of the key guidelines.
In analyzing the previous guidelines, the Health and Human Services Department also found that, between 2011 and 2015, only about 30 percent of male and 15 percent of female high school students met the the requirements for both aerobic physical activity and muscle-strengthening.
Annual sample sizes of between 6,000 to 7,000 students for each group were surveyed annually. In determining aerobic activity, students were asked if they completed at least 60 minutes of "any kind of physical activity that increases your heart rate and makes you breathe hard some of the time" every day in the week before the survey. In meeting the muscle-strengthening component, students were asked if, as part of the 60 minutes, they did "exercises to strengthen or tone your muscles" at least three days in the week before.
"Sports participation declines as youth enter middle and high school, and there are particular barriers—including costs—that limit participation in youth sports, especially among minorities, girls, and low-income youth," Assistant Secretary for Health Brett Giroir says in a statement accompanying the guidelines.
Preschool-age children were also included in the report for the first time in 2018. According to the guidelines, a reasonable target for 3- to 5-year-olds is three hours per day.
"Parents and caregivers can have a critical role in supporting and encouraging young children to be physically active and in modeling participation in regular physical activity," the report says.
This year's report specifies the following health benefits associated with regular physical activity, based on its evidence review:
- Improved bone health (ages 3 through 17)
- Improved weight status (ages 3 through 17)
- Improved cardiorespiratory and muscular fitness (ages 6 through 17)
- Improved cardiometabolic health (ages 6 through 17)
- Improved cognition (ages 6 to 13)
- Reduced risk of depression (ages 6 to 13)
Graph courtesy of The Journal of the American Medical Association